An ink jet printer prints patterns according to an input signal corresponding to an image or text. The ink jet printer includes, for example, an ink jet head and an ink jet head control circuit that controls the ink jet head. The ink jet head includes an actuator for ejecting ink and a driver integrated circuit (IC) that drives the actuator according to a control signal input from the ink jet head control circuit.
An ink jet head may include a non-volatile memory that stores unique information of the ink jet head, maintenance information, and the like. When a non-volatile memory is mounted on the ink jet head, the ink jet head control circuit also requires a connection terminal for accessing the non-volatile memory. However, adding such a terminal to the inkjet head control circuit and the inkjet head may increase costs.